src/main/java/no/uib/inf101/terminal/CommandLineInterface.java

 package no.uib.inf101.terminal;
 
+// UiB INF101 ShellLab - CommandLineInterface.java
+//
+// Grensesnittet CommanLineInterface beskriver metoder for input og
+// output til et program som virker med et tekstbasert grensesnitt.
+// Du trenger ikke gjøre noen endringer i denne filen for denne lab'en.
+
 /**
  * A command line interface is a program with a text-based user interface.
  * The user can enter keys as input, and the program will respond by giving
@@ -10,13 +16,14 @@ public interface CommandLineInterface {
   /**
    * Called when a key is pressed.
    *
-   * @param key The key that was pressed
+   * @param key  the key that was pressed
    */
   void keyPressed(char key);
 
   /**
    * Get the text to display on the screen.
-   * @return The text to display
+   *
+   * @return  the text to display
    */
   String getScreenContent();
 }

src/main/java/no/uib/inf101/terminal/Context.java

 package no.uib.inf101.terminal;
 
+// UiB INF101 ShellLab - Context.java
+//
+// Denne filen inneholder kode som navigerer et filsystem. Du trenger
+// ikke gjøre noen endringer i denne filen for denne lab'en (med mindre
+// du selv ønsker).
+
 import java.io.File;
 import java.io.IOException;
 import java.util.Objects;
 
 public class Context {
 
+  ////////////////////////
+  // Instance variables
+  ////////////////////////
   private final File home;
   private File cwd;
 
+  ////////////////////////
+  // Constructors
+  ////////////////////////
+
+  /**
+   * Create a new context with the java current working directory as
+   * home.
+   */
+  public Context() {
+    this(new File(System.getProperty("user.dir")));
+  }
+
+  /**
+   * Create a new context with the given directory as home.
+   *
+   * @param home  the home directory.
+   */
   public Context(File home) {
     try {
       this.home = home.getCanonicalFile();
@@ -18,27 +44,50 @@ public class Context {
     }
   }
 
+  ////////////////////////
+  // Instance methods
+  ////////////////////////
+
+  /**
+   * Go to the given path, if it exists. The path can be relative to
+   * the current working directory, or absolute.
+   *
+   * @param path  the path to go to.
+   * @return  true if the path exists, false otherwise
+   */
   public boolean goToPath(String path) {
-    File newDir = new File(cwd, path);
+    File newDir = new File(this.cwd, path);
     if (!newDir.isDirectory()) {
       return false;
     }
     try {
-      cwd = newDir.getCanonicalFile();
+      this.cwd = newDir.getCanonicalFile();
+      return true;
     } catch (IOException e) {
       throw new RuntimeException(e);
     }
-    return true;
   }
 
+  /**
+   * Get the current working directory.
+   *
+   * @return  the current working directory.
+   */
   public File getCwd() {
     return this.cwd;
   }
 
+  /** Set the current working directory to the home directory.*/
   public void goToHome() {
     this.cwd = this.home;
   }
 
+  /**
+   * Check if the current working directory is the home directory.
+   *
+   * @return  true if the current working directory is the home
+   *          directory, false otherwise.
+   */
   public boolean isAtHome() {
     return Objects.equals(this.cwd, this.home);
   }

src/main/java/no/uib/inf101/terminal/DummyShell.java

 package no.uib.inf101.terminal;
 
+// UiB INF101 ShellLab - DynamicShell.java
+//
+// Denne koden er gitt som et eksempel på en klasse som implementerer
+// CommandLineInterface. Du trenger ikke gjøre noen endringer i denne
+// filen for denne lab'en (med mindre du selv ønsker).
+
 public class DummyShell implements CommandLineInterface {
 
   private String screenContent = "$ ";
 
   @Override
-  public void keyPressed(char keyCode) {
-    if (keyCode == '\n') {
+  public void keyPressed(char key) {
+    if (key == '\n') {
       screenContent += "\n$ ";
     } else {
-      screenContent += keyCode;
+      screenContent += key;
     }
   }
 

src/main/java/no/uib/inf101/terminal/EchoShell.java

 package no.uib.inf101.terminal;
 
+// UiB INF101 ShellLab - EchoShell.java
+//
+// Denne koden er gitt som et eksempel på en klasse som implementerer
+// CommanLineInterface. Du trenger ikke gjøre noen endringer i denne
+// filen for denne lab'en (med mindre du selv ønsker).
+
 import java.util.ArrayList;
 
 public class EchoShell implements CommandLineInterface {
@@ -7,13 +13,13 @@ public class EchoShell implements CommandLineInterface {
   String currentLine = "";
 
   @Override
-  public void keyPressed(char keyCode) {
-    if (keyCode == '\n') {
+  public void keyPressed(char key) {
+    if (key == '\n') {
       outputLines.add("$ " + currentLine);
       outputLines.add("Oh, an echo! listen: " + currentLine);
       currentLine = "";
     } else {
-      currentLine += keyCode;
+      currentLine += key;
     }
   }
 

src/main/java/no/uib/inf101/terminal/Main.java

 package no.uib.inf101.terminal;
 
+// UiB INF101 ShellLab - Main.java
+// Dette er filen som inneholder main-metoden.
+
 public class Main {
 
   public static void main(String[] args) {

src/main/java/no/uib/inf101/terminal/SimpleShell.java

 package no.uib.inf101.terminal;
 
+// UiB INF101 ShellLab - SimpleShell.java
+//
+// Dette er klassen vi skal forbedre i denne lab'en. Slik koden er
+// allerede før du begynner på laben, støtter den tre kommandoer:
+//
+// - cd: Bytt til en annen mappe
+// - ls: List opp filer i mappen
+// - pwd: Vis sti til nåværende mappe
+//
+// Vi skal endre denne klassen slik at den
+// - kan vises av Terminal.java
+// - kan støtte ubegrenset mange kommandoer
+
 import java.io.File;
 import java.util.ArrayList;
+import java.util.List;
 import java.util.Objects;
 
-// TODO: Let SimpleShell implement CommandLineInterface
+// TODO 1: Let SimpleShell implement CommandLineInterface
 public class SimpleShell {
 
   //////////////////////////////////////////////////////////////////////
@@ -14,24 +28,24 @@ public class SimpleShell {
   /** The prompt to show before each command */
   private final String prompt = "$ ";
   /** The context variable contains cwd and home directories etc. */
-  private final Context context = new Context(
-      new File(System.getProperty("user.dir"))
-  );
+  private final Context context = new Context();
   /** A list of historic commands and their outputs */
-  private final ArrayList<String> history = new ArrayList<>();
+  private final List<String> history = new ArrayList<>();
   /** The command currently being typed */
   private String currentCommand = "";
+  // TODO 4: Create instance variable storing Command objects
 
   //////////////////////////////////////////////////////////////////////
-  /// Public methods                                              //////
+  /// Public instance methods                                     //////
   /// (methods expected to be used by someone outside this class) //////
   //////////////////////////////////////////////////////////////////////
 
+  /** Constructor for SimpleShell */
   public SimpleShell() {
-    // TODO: Install core commands SimpleShell supports (pwd, ls, cd)
+    // TODO 7-8-9: Install core commands SimpleShell supports (pwd, ls, cd)
   }
 
-  // TODO: rename method to fit new interface, annotate with @Override
+  // TODO 2: rename method to fit new interface, annotate with @Override
   // Note: methods with @Override generally do not need javadoc comments,
   // since the javadoc comment is inherited. You should hence remove the
   // javadoc comment here unless there is something special about this
@@ -46,10 +60,12 @@ public class SimpleShell {
       this.processCurrentCommandLine();
     } else if (key >= ' ' && key <= '~') {
       this.currentCommand += key;
+    } else {
+      // Some special key was pressed (e.g. shift, ctrl), we ignore it
     }
   }
 
-  // TODO: rename method to fit new interface, annotate with @Override
+  // TODO 3: rename method to fit new interface, annotate with @Override
   /**
    * Get the text which the terminal should display
    *
@@ -65,6 +81,8 @@ public class SimpleShell {
     return s;
   }
 
+  // TODO 5: Add method to install a command
+
   //////////////////////////////////////////////////////////////////////
   /// Private methods                                ///////////////////
   /// (helper methods used internally in this class) ///////////////////
@@ -102,7 +120,8 @@ public class SimpleShell {
    * @return  The output of the command
    */
   private String executeCommand(String commandName, String[] args) {
-    // TODO: Change sequence of if/else if below to a lookup in a map
+    // TODO 6: Call run on Command object for given commandName if present
+    // TODO 7-8-9: Remove if's for cd, ls, pwd once installed as commands
     if (Objects.equals(commandName, "pwd")) {
       return this.doPwd(args);
     } else if (Objects.equals(commandName, "cd")) {
@@ -114,12 +133,12 @@ public class SimpleShell {
     }
   }
 
-  // TODO: remove this method and replace it with Command -type object
+  // TODO 7: remove this method and replace it with Command -type object
   private String doPwd(String[] args) {
     return this.context.getCwd().getAbsolutePath();
   }
 
-  // TODO: remove this method and replace it with Command -type object
+  // TODO 8: remove this method and replace it with Command -type object
   private String doCd(String[] args) {
     if (args.length == 0) {
       this.context.goToHome();
@@ -135,7 +154,7 @@ public class SimpleShell {
     }
   }
 
-  // TODO: remove this method and replace it with Command -type object
+  // TODO 9: remove this method and replace it with Command -type object
   private String doLs(String[] args) {
     File cwd = this.context.getCwd();
     String s = "";

src/main/java/no/uib/inf101/terminal/Terminal.java

 package no.uib.inf101.terminal;
 
+// UiB INF101 ShellLab - Terminal.java
+//
+// Denne filen inneholder kode som tegner et vindu på skjermen, som
+// viser et CommandLineInterface -program. Du er ikke forventet å
+// forstå denne koden denne uken, og du trenger ikke gjøre noen
+// endringer i denne filen for denne lab'en (med mindre du selv ønsker).
+
 import javax.swing.*;
 import java.awt.*;
 import java.awt.event.KeyAdapter;
 import java.awt.event.KeyEvent;
 
+/**
+ * A simple terminal GUI for interacting with command line interfaces.
+ */
 public class Terminal extends JPanel {
-  private final CommandLineInterface terminal;
+  ////////////////////////
+  // Instance variables
+  ////////////////////////
+  /** The command line interface to interact with. */
+  private final CommandLineInterface cli;
 
+  ////////////////////////
+  // Constructor
+  ////////////////////////
+  /** Create a new terminal GUI for the given command line interface. */
   public Terminal(CommandLineInterface cli) {
-    this.terminal = cli;
+    this.cli = cli;
     this.setPreferredSize(new Dimension(400, 300));
     this.setFocusable(true);
     this.addKeyListener(new KeyAdapter() {
       @Override
       public void keyPressed(KeyEvent e) {
-        Terminal.this.terminal.keyPressed(e.getKeyChar());
+        Terminal.this.cli.keyPressed(e.getKeyChar());
         Terminal.this.repaint();
       }
     });
   }
 
-
+  ////////////////////////
+  // Instance methods
+  ////////////////////////
   @Override
   public void paintComponent(Graphics g) {
     super.paintComponent(g);
-    String content = this.terminal.getScreenContent();
-
-    // Calculate number of lines that can fit display
-    int lineHeight = g.getFontMetrics().getHeight() + 5;
-    int lines = this.getHeight() / lineHeight;
 
-    // Draw the text on the screen, line by line
     g.setColor(Color.BLACK);
     g.setFont(new Font("Monospaced", Font.PLAIN, 12));
-    int y = lineHeight;
+    int lineHeight = g.getFontMetrics().getHeight() + 2;
 
-    // Iterate through the last 'lines' lines of the content
-    String[] linesOfContent = content.split("\n");
-    for (int i = Math.max(0, linesOfContent.length - lines); i < linesOfContent.length; i++) {
-      g.drawString(linesOfContent[i], 5, y);
+    // Tegn teksten på skjermen, linje for linje. Potensiell forbedring:
+    // hvis det er for mange linjer, vis kun de siste av dem.
+    String content = this.cli.getScreenContent();
+    int y = 20;
+    for (String line : content.split("\n")) {
+      g.drawString(line, 5, y);
       y += lineHeight;
     }
   }
 
+  /** Run the terminal GUI in a window frame. */
   public void run() {
     JFrame frame = new JFrame("INF101 Terminal");
     frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

src/main/java/no/uib/inf101/terminal/TextAnswers.java

 package no.uib.inf101.terminal;
 
+// UiB INF101 ShellLab - TextAnswers.java
+//
+// I denne filen skal du besvare spørsmålene under. Du kan sjekke
+// svarene dine ved å kjøre testen TextAnswersTest.java.
+
 public class TextAnswers {
 
-  /*
+  /**
    * Consider the following code:
-   *
    * CommandLineInterface cli = new DummyShell();
+   *
+   * What is the type of the variable cli?
    */
-  /** What is the type of the variable cli? */
   static final String q1 = "";
 
-  /** In which class is the object cli refers to? */
+  /**
+   * Consider the following code:
+   * CommandLineInterface cli = new DummyShell();
+   *
+   * In which class is the object cli refers to?
+   */
   static final String q2 = "";
 
-  /** True or false: CommandLineInterface is both a type and an interface. */
+  /**
+   * Consider the following code:
+   * CommandLineInterface cli = new DummyShell();
+   *
+   * true or false: CommandLineInterface is both a type and an interface.
+   */
   static final Boolean q3 = null;
 
-  /** True or false: DummyShell is both a class and a type. */
+  /**
+   * Consider the following code:
+   * CommandLineInterface cli = new DummyShell();
+   *
+   * true or false: DummyShell is both a class and a type.
+   */
   static final Boolean q4 = null;
 
 }